Cardiac Impulse Sensor for Presence Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional pyroelectric infrared sensors fail to detect individuals moving at low speeds or stopped, are prone to interference from temperature variations, and cannot sense beyond a predetermined optic angle, leading to inaccurate presence detection and increased production costs.
Innovation Solution
A non-contact cardiac impulse sensor and wireless processing unit are employed to generate and transmit operation signals for electronic devices, allowing for accurate detection of human presence and presence state, enabling control of devices like lighting and air conditioning, and reducing power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a pyroelectric infrared ray sensor is used to detect human presence, then the sensor can detect temperature differences from moving human bodies, but it fails to detect persons moving at low speed or stopped and is prone to interference from temperature variations
Solution Approach 1:
The patent segments the detection function into two independent sensors: a pyroelectric infrared sensor for detecting temperature differences and a cardiac impulse sensor for detecting heartbeats. This segmentation allows each sensor to specialize in one type of detection, improving overall reliability by compensating for the limitations of the pyroelectric sensor when persons are stationary or moving slowly.
Solution Approach 2:
The cardiac impulse sensor acts as an intermediary detection mechanism that complements the pyroelectric sensor. When the pyroelectric sensor fails to detect stationary persons, the cardiac impulse sensor detects heartbeats through the chair, serving as a mediator to confirm presence and eliminate false negatives.
2Area of stationary object
If the sensing angle of the pyroelectric infrared ray sensor is increased by using a Fresnel optical lens, then the optic angle coverage is improved, but the sensor still cannot sense beyond a predetermined range within the line of sight
Solution Approach 1:
The patent merges two different sensing technologies (pyroelectric infrared sensing and cardiac impulse sensing) into a single integrated system. The cardiac impulse sensor detects vibrations through the chair regardless of the person's position or movement, complementing the optical lens-based pyroelectric sensor and extending the effective detection range beyond the predetermined optic angle limitations.
3Device complexity
If conventional pyroelectric infrared sensors are used for presence detection, then the system structure is simple, but production costs increase and detection accuracy decreases
Solution Approach 1:
The integrated sensor system achieves multi-functionality by combining presence detection (pyroelectric sensor), stationary detection (cardiac impulse sensor through chair), and fall detection (abnormal heartbeat pattern recognition) capabilities. This universal system replaces multiple separate sensors with a unified platform that improves detection accuracy across various scenarios while managing system complexity through integrated processing.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution improves detection accuracy, reduces production costs, and enables efficient control of electronic devices based on presence and sleep states, optimizing power usage in home network systems.
Implementation Method 1
the variation in an electric field resulting from the movement of muscles of the person according to the cardiac impulse or the respiration of the person is detected
Data Source
AI summary
Disclosed are a sensor, which includes a cardiac impulse sensor for sensing a cardiac impulse of a human body spaced apart from the cardiac impulse sensor to generate an output signal, and a wireless processing unit for processing and outputting an operation signal of an electronic device according to an output signal of the cardiac impulse sensor, a network system including the sensor, and a method of controlling an electronic device. The electronic device is effectively controlled.